Hello, I have gone through your query and understood the concern. In a 28-day cycle, ovulation will occur on the 14th day, i.e., 14 days before the onset of the next period. Spermatozoa remain active for 3-5 days after ejaculation; please remember that even the pre-ejaculate contains enough sperm to cause conception during the ovulation or fertile period. Though you had the intercourse around the fertile period, the chances of conception are very less considering the fact that it was slightly far from the probable date of ovulation and also since the emergency contraception was taken. Though the protection offered with the pill decreases with time span, yet a good amount of protection is offered. She may see some withdrawal bleeding a few days after the pill and her next natural period may get delayed by a week or two. Please do not stress; just see a specialist for further help if she becomes overdue by ten days. Take care.